Plaster board



June 22 `1926.

J. STRAND PLASTER BOARD Filed June 25. 1924 Patented .lune 22, 1926.

UNITED STATES 1,589,724 PATENT oFFlcE.

` ,JOSEPH STRAND, OF LOS ANGELES, CALIFORNIA, ASSIGNOR TO dKLINCBI LATE COR- PORATION, A CORPORATION OF CALIFORNIA.

:BLASTER BOARD.

Application led June 25, 1924. Serial No. 722,266,

My present invention is referred to as a staple-key plaster board for the reason that it involves the use of metallic fastening devices, such as ordinary staples, preferably extending across slots, of-any usual or preferred character, in a plaster board adapted to be provided with an additional coating, such as an inner finishing coat or` an outer protective coat; and it is an object of this invention to provide simple and effective means serving not only to offset any weakening effect arising from the provision of key slots or depressions in plaster board, but serving also and more especially to aid in the retention of the key of a coating material within such slots or depressions, regardless of whether such slots are formed with inclined or with perpendicular walls, and regardless of whether or not they are formed by a cutting operation executed upon apreformed slab.

This invention relates particularly to a plasterboard structure in which staples, or the like, are employed, in con' notion with slots preformed in a plaster oard, to aid in the retention of `a coating thereon; and said plaster board may comprise a slab of plastic material, of any usual or preferred character, provided on one or both of its substantially flat faces with a sheet of fibrou's material such as paper, outside of which my reinforcing and key-retaining devices such as staples extendln across the` mentioned slots, may be clinche Other ob'ects of my invention will appear from the ollowin description of an advantageous embodlment thereof, taken in connection with the appended claims and the accompanying drawings, in which Fig. 1 is a erspective view of a corner of a slab of p aster board embodying the features of my present invention.

Fig. 2 is a vertical or transverse section in a plane such as is indicated by the line 2--2 of Fig. 1, a coating being indicated as applied and keyed to said slab.

Referring to the details of that specific embodiment of my invention chosen for purposes of illustration, 11 may be a body of plastic material` to the opposite` faces of which layers 12, 12 of pa er or a similar fibrous material are prefera ly applied, slots 13, 13 being shown as arranged in separate linear series with their longitudinal axes extending substantially at right angles, and

each slot being provided with a staple or staples 14, shown as extendin thereacross. The respective slots may be of' any desired depth and configuration, although it will be obvious that, if wall paper is to be applied directly t0 one surface of my wall board, the mentioned slots should not extend entirely therethrough, and obvious also that, in the case referred to, the points of the staples 14, or their equivalent, should not be permitted to roject beyond the inner or smooth surface o said plaster board. v

I consider it advanta eous, in order to utilize the staples 14, ort eir equivalent for both a reinforcing and a keying effect in the retention of a coating- 15, or its equivalent, to provide the same with comparatively sharp points 16, and to rebend or clinch these points in such manner as to preserve the smoothness of the lower or inner surface, shown as provided with the mentioned layer of fibrous material 12', through which said points/ extend. By this construction, it will be obvious that, whether or not the slots 13, 13 are under-cut, the key projections 17, or their equivalent, are so retained as to prevent the separation of the coating 15, without an actual breakage of said ke projections.

Stap s extending sli htly above the laster board may optiona ly be used wit out slots;l and although I have herein described one complete embodiment of my invention, it will be understood that various features thereof might be independently employed, and also that various modicatious'mlght be made by those skilled in the art, without the slightest departure from the spirit and scope of my invention, as the same -is indicated above and in the following claims.

I claim as my invention:

1. A plaster board comprising: a slab of plastic material having key slots formed in.

the face thereof, said slots having side walls substantially perpendicular to said face; and individual metallic fastening devices extending across said slots. p

21A plasterboard comprising: a slab of plastic material having key slots formed in the face thereof, said slots having side walls substantially perpendiculart to said face and said slots being arranged in series with their" lon 'tudinal axes extending in a plurality of tening devices extending across said slots.

irections; and individual metallic fas-v said slots being arranged in series with theirv 3. A plaster board comprising: a slab of plastic material having key slots formed in the face thereof, said slots having side walls substantially perpendicular to said face and longitudinal axes extending in a plurality of devices extending transversely across sai slots.

4. A plaster board comprising: a slab of stapleskvdriven partially into said slab and directions; and individual metallic fastenin having their horizontal portions bridging said slots.

5. A plaster board comprising: a body of plastic material having recesses formed therein, said recesses conforming in outline to a segment of a disc; and individual metallic laster retaining devices extending across sai recesses, said devices consisting of staples driven into said body and the ends clinched therein.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 12th day of June, 1924.

JOSEPH STRAND. 

